We propose to develop a prospective longitudinal database that is tailored to the special requirements for addressing medical effectiveness questions in Type II diabetes. No database presently exists to address these issues adequately. In contrast to Type I diabetics, blood glucose control is less salient. Therefore we will utilize quality of life measures, not the long-term prevention of complications, as the appropriate outcome measure for assessing medical effectiveness for Type II diabetes care. We will study the financial costs to the health system and to the patient, as well as the effect of blood glucose control and the early detection and treatment of complications on the patients' quality of life. Specifically, we propose to develop a comprehensive database for the monitoring of costs, quality and outcomes of care for patients with Type II diabetes in three large health care delivery organizations. These organizations are diverse in their geography and systems of care as well as the socioeconomic status of their patients. We will relate utilization and expenditures for patients with Type II diabetes to blood glucose control, and the detection and treatment of complications, and to health-related quality of life. We will relate the quality of technical care measured by adherence to guidelines and the quality of interpersonal care assessed by the patient, to utilization and expenditures, as well as health-related quality of life. We will derive guidelines and define optimal technical and interpersonal care based on literature review, decision analyses and subsequently on the database. We will monitor variations in care relative to these guidelines and the impact that this variation has on outcomes. Based on information from the database, we will develop and test interventions designed to change specific physician behaviors with respect to utilization and expenditures, as well as technical and interpersonal quality of care. In summary, this proposal features: 1.A data system endorsed and supported by the organized practice settings themselves, maximizing the opportunity for use in routine office practice to monitor and improve patient care. 2.A team of investigators with considerable experience in primary data collection of the type proposed for construction of this database. 3.Use of well developed and tested measures of clinical outcomes and case mix adjustment. 4 Development of guidelines in the institution of interventions and aimed at changing specific physician behaviors. These features will enable us to answer major questions about the effectiveness of care for Type II diabetes and to translate these answers into strategies that will decrease costs and increase the quality of care for these patients.